CDC is closely tracking cases of monkeypox that have been reported since mid-May in the United States and many other countries without a history of monkeypox activity, including in Europe, the Americas, the Middle East, Asia, Australia, and some countries in Africa. Eviidence indicates that the virus is spreading mostly through close, personal, often skin-to-skin contact with someone who has monkeypox. On July 23, the World Health Organization (WHO) declared monkeypox a Public Health Emergency of International Concern (PHEIC). This is WHO’s highest level of global alert, and the decision recognizes the potential threat this virus poses to countries around the world. CDC is supportive of this decision, as it can serve to move the international community to more quickly and effectively respond to and combat this virus.